qapi: Require valid names

Previous commits demonstrated that the generator overlooked various
bad naming situations:
- types, commands, and events need a valid name
- enum members must be valid names, when combined with prefix
- union and alternate branches cannot be marked optional

Valid upstream names match [a-zA-Z][a-zA-Z0-9_-]*; valid downstream
names match __[a-zA-Z][a-zA-Z0-9._-]*.  Enumerations match the
weaker [a-zA-Z0-9._-]+ (in part thanks to QKeyCode picking an enum
that starts with a digit, which we can't change now due to
backwards compatibility).  Rather than call out three separate
regex, this patch just uses a broader combination that allows both
upstream and downstream names, as well as a small hack that
realizes that any enum name is merely a suffix to an already valid
name prefix (that is, any enum name is valid if prepending _ fits
the normal rules).

We could reject new enumeration names beginning with a digit by
whitelisting existing exceptions.  We could also be stricter
about the distinction between upstream names (no leading
underscore, no use of dot) and downstream (mandatory leading
double underscore), but it is probably not worth the bother.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

tests/qapi-schema/bad-ident.err

@@ -0,0 +1 @@
+tests/qapi-schema/bad-ident.json:2: 'type' does not allow optional name '*oops'

tests/qapi-schema/bad-ident.exit

@@ -1 +1 @@
-0
+1

tests/qapi-schema/bad-ident.json

@@ -1,2 +1,2 @@
-# FIXME: we should reject creating a type name with bad name
+# we reject creating a type name with bad name
 { 'type': '*oops', 'data': { 'i': 'int' } }

tests/qapi-schema/bad-ident.out

@@ -1,3 +0,0 @@
-[OrderedDict([('type', '*oops'), ('data', OrderedDict([('i', 'int')]))])]
-[]
-[OrderedDict([('type', '*oops'), ('data', OrderedDict([('i', 'int')]))])]

tests/qapi-schema/enum-bad-name.err

@@ -0,0 +1 @@
+tests/qapi-schema/enum-bad-name.json:2: Member of enum 'MyEnum' uses invalid name 'not^possible'

tests/qapi-schema/enum-bad-name.exit

@@ -1 +1 @@
-0
+1

tests/qapi-schema/enum-bad-name.json

@@ -1,2 +1,2 @@
-# FIXME: we should ensure all enum names can map to C
+# we ensure all enum names can map to C
 { 'enum': 'MyEnum', 'data': [ 'not^possible' ] }

tests/qapi-schema/enum-bad-name.out

@@ -1,3 +0,0 @@
-[OrderedDict([('enum', 'MyEnum'), ('data', ['not^possible'])])]
-[{'enum_name': 'MyEnum', 'enum_values': ['not^possible']}]
-[]

tests/qapi-schema/enum-dict-member.err

@@ -1 +1 @@
-tests/qapi-schema/enum-dict-member.json:2: Enum 'MyEnum' member 'OrderedDict([('value', 'str')])' is not a string
+tests/qapi-schema/enum-dict-member.json:2: Member of enum 'MyEnum' requires a string name

tests/qapi-schema/flat-union-bad-discriminator.err

@@ -1 +1 @@
-tests/qapi-schema/flat-union-bad-discriminator.json:11: Flat union 'TestUnion' discriminator must be a string
+tests/qapi-schema/flat-union-bad-discriminator.json:11: Discriminator of flat union 'TestUnion' requires a string name

tests/qapi-schema/flat-union-optional-discriminator.err

@@ -0,0 +1 @@
+tests/qapi-schema/flat-union-optional-discriminator.json:6: Discriminator of flat union 'MyUnion' does not allow optional name '*switch'

tests/qapi-schema/flat-union-optional-discriminator.exit

@@ -1 +1 @@
-0
+1

tests/qapi-schema/flat-union-optional-discriminator.json

@@ -1,4 +1,4 @@
-# FIXME: we should require the discriminator to be non-optional
+# we require the discriminator to be non-optional
 { 'enum': 'Enum', 'data': [ 'one', 'two' ] }
 { 'type': 'Base',
   'data': { '*switch': 'Enum' } }

tests/qapi-schema/flat-union-optional-discriminator.out

@@ -1,7 +0,0 @@
-[OrderedDict([('enum', 'Enum'), ('data', ['one', 'two'])]),
- OrderedDict([('type', 'Base'), ('data', OrderedDict([('*switch', 'Enum')]))]),
- OrderedDict([('type', 'Branch'), ('data', OrderedDict([('name', 'str')]))]),
- OrderedDict([('union', 'MyUnion'), ('base', 'Base'), ('discriminator', '*switch'), ('data', OrderedDict([('one', 'Branch'), ('two', 'Branch')]))])]
-[{'enum_name': 'Enum', 'enum_values': ['one', 'two']}]
-[OrderedDict([('type', 'Base'), ('data', OrderedDict([('*switch', 'Enum')]))]),
- OrderedDict([('type', 'Branch'), ('data', OrderedDict([('name', 'str')]))])]

tests/qapi-schema/union-optional-branch.err

@@ -0,0 +1 @@
+tests/qapi-schema/union-optional-branch.json:2: Member of union 'Union' does not allow optional name '*a'

tests/qapi-schema/union-optional-branch.exit

@@ -1 +1 @@
-0
+1

tests/qapi-schema/union-optional-branch.json

@@ -1,2 +1,2 @@
-# FIXME: union branches cannot be optional
+# union branches cannot be optional
 { 'union': 'Union', 'data': { '*a': 'int', 'b': 'str' } }

tests/qapi-schema/union-optional-branch.out

@@ -1,3 +0,0 @@
-[OrderedDict([('union', 'Union'), ('data', OrderedDict([('*a', 'int'), ('b', 'str')]))])]
-[{'enum_name': 'UnionKind', 'enum_values': None}]
-[]